Belt-joint.



I J. c. BLEVNEY.

BELT JOINT.

APPLICATION FILED-DEG. 29, 1908.

944,658, Patented Dec.28,1909.

f X E B;Q 7,

WW VA *7 7 W 7 & W W 2% A JOHN C. BLEVNEY, F NEWARK, NEW JERSEY.

- BELT-JOINT.

aaa'ess.

Specification of Letters Patent. at t 2 19 9 Application filed December29, 1908. Serial No. 469369.

To all whom it may concern:

Be it known that I, JOHN C. BLEVNEY, a citizen of the United States ofAmerica, residing at Newark, in the county of Essex and State of NewJersey, have invented certain new and useful Improvements in BeltJoints, of which the following is a specification, reference being hadtherein to the accompanying drawing.

My invention relates to endless belts adapted for use in polishing andgrinding metal and other surfaces, such belts, as those having a smoothback which travels over pullleys and an abrasive face which does thewort. I

My object is to provide a better joint where the ends of the belt arefastened together, so that the belt will be the same thicknessthroughout and have a more uniform back surface and abrasive face.

To this-end my invention consists in the peculiar features andcombinations of parts more fully described hereinafter and pointed outin the claims.

ln the accompanying drawings, Figure 1 represents the two opposite endsof the face of my abrasive belt in position for the fingers thereon tobe brought together and fas-' tened. Fig. 2, a perspective view thereofafter the edges of the ends have been brought together before thefingers are pressed down and fastened to the back. Fig. 3, a plan viewof the face of the belt afterthe fingers have been pressed down flushwith the back surface thereof, the zigzag line showing the form of thejoint, and Figs. 4 and 5 are enlarged transverse and longitudinal sec-.tions respectively through'lines w, w and y, y

of Fig. 3, showing the overlapping fingers embedded in the back of themeeting portions of the solid belt. Y

My improved joint is adapted to be ap:

plied 'to all belts used for grinding and polishing and especially tothose endless abrasive belts made principally out of emery or abrasivecloth which is always more or less filled with Inc, or other adhesivematter to engage and hold the ground of pulverized abrasive on the faceof the belt and to strengthen the fabric, the back of the belt beingsmooth. Joints for belts of this kind have heretofore been made invarious ways such as by cutting the ends of the belt ofi', eithersquarely or diagonally, butting them together and securing them so by apatch glued or cemented on the back of the belt over the butting ends,whereby the face carrylng the abrasive surface of the belt will be flushat the joint.

' An endless grinding or polishing belt 3 area in order to securesufficient tensile g strength. Such big patches add to the thickness ofthe belt and render the joint easily cut at the edges of the patch andeasily torn while in use. Furthermore, such extra thickness makes thebelt less pliable and more diflicult for the operator to bring the workto a proper size when such is desired, because at a certain stage of theprocess the high point of the belt at the joint acts like a cam and willbe the only part to take eifect upon the work. Generally this high-pointhas all or most of the abrasive surface worn off long before theremainder is used up. Another disadvantage growing out of the use ofsolid patches, having a large area, is that they cannot be pressed downto lie flush with the surface of the belt without using excessivepressure to an extent of destroying the strength of the fabric. Stillanother disadvantage lies inthe rapid wearing away of the butting edgesof the belt where they meet at the middle of the patch. There ore, it isapparent that an endless abrasive belt should have a joint that is nothicker than the material out of which the belt is made.

To overcome the foregoing difiiculties and produce such a belt, Idispense with the bac'l -patch and make a substantially amalgamatedflush joint out of the belt itself by forming peculiar longitudinalfingers 1 in the oppos'ingends 2 of the belt 3. Intervening' spaces 4are formed between the fingers and are a counterpart of the latter.Hence itwillbe seen that in cutting belts from the cloth the cutting outof the fingers on one belt will leave counterpart receiving spaces forthe fingers in the next belt cut,

said spaces andfingers being of the same size and shape, excepting thetwo outside fingers 5 on one of the ends of thebelt, which fingers arehalf-fingers. This formation allows the fingers to freely pass oneanother in the act of bringing the abutting ends of the belt together,and it also leaves room between the fingers to receive material that iscrowded out from under them when the fingers are spread .laterally andpressed down and embedded into the back of the beli proper. Preferablyall the finge s are w vided with taperedpoints 6 and the interveningspaces 4 with correspondingly tapered throats 7. Each finger is bypreference oblong with straight parallel edges 8 terminatingrespectively at the base of the tapered point 6 and at the base 10 ofthe.

preferably with a piece of felt, cloth orblotting paper soaked in hotwater or steam, of a Width. to cover the fingers and of the properthickness to hold the right amount of moisture. This should be pressedlightly on the joint and then removed. Pressure is now brought to bearupon the overlapping fingers, generally enough to press the fingers intothe belt to a flush surface. No cement or glue other than that alreadyin the cloth is necessary, the moisture applied having softened theglue. This pressure may vary according to the grade of goods, thecoarser requiring generally less than the finer rade. It is often foundconvenient and deslrable to put hard oiled pasteboard over the back ofthe joint in the press in order to bring the cloth to a flush grindingsurface. By my construction and process I am able to effect a strongneat flush joint without the use of glue or patch, and I bring'theextreme ends of the belt to the back thereof. Furthermore there is noperceptible reduction in the strength or the bending or breakinqualities of the fabric, and the joint is re uced to the same orsubstantiallythe same thickness as that of the remainder of the belt,and the premature wearing off of the abrasive surface at the joint isalmost, if notcompletely, prevented. By using the baclzlapping andembedding construction there is only asmall bod of double-thickness tospread and press into the adjoining fabric of the belt and enoughpressuremay the fabric.

- The advantages of'having the ends of the fingers and'the throats ofthe recesses between the fingers tapered to a longitudinal point wherethe fingers and throats come together is that the edges of the beltfabric will lie in.oblique relati on to the path of travel of the belt,and consequently bring the edges of the throats diagonally against theprojections on the work to be finished. This contact is most severeafter the abrasive material on the face of the belt has worn offconsiderably, and if the joint extended at right angles to the path oftravel, the edge of the cloth would wear away much more rapidly. It isalso apparent that glue or other binders must be used if the materialfrom which the belts are made is not already charged with it, and thatother changes in the form and process of carrying out my device might beresorted to without departing from thescope and spirit of the appendedclaims therefore I do not wish to limit myself to the exact detailsherein described and shown. r

Having thus described my invention, what I claim is: v

1. A flush-joint. for abrasive belts, which joint consists of aplurality of embedded and back-lapped fingers at the attaching ends ofthe belt.

2. A joint for belts, which joint consists of .a plurality oflongitudinal fingers provided with points or tapered ends and separatedby corresponding longitudinal spaces having tapered throats adapted toreceive the bases of the fingers, said fingers being crossed and closedat the throats and lapjoined to and embedded to lie flush with the backof the ends of the belt.

3. A joint for abrasive belts impregnated with glue, which jointconsists of oppositely projecting integral fingers crossed and closed atthe throats, and folded down and lapjoined to the back of the contiguousends of the belt by the adhesive substance in the belt.

In testimony whereof I afiix my signature in presence of two witnesses.

J OHN', C. BLEVNEY. Witnesses:

R. G. DU 13018, C. B. SICHROEDER.

